Dip tube supporting means which is locked against axial movement



June 12, 1962 F. v. BOYLAN 3,038,744 DIP TUBE SUPPORTING MEANS WHICH ISLOCKED AGAINST AXIAL MOVEMENT Filed May 26 1958 INVENTOR Frank V. BoylanBy: j

' fl-TT/S- a Unite States partnership of Louisiana Filed May 26, 1958,Ser. No. 737,9il6 2 Claims. (Cl. 285-142) This invention relatesgenerally to water heating devices of the storage type and is directedparticularly to improvements in the supporting means for dip tubesforming a part of such water heaters.

Automatic storage water heaters embody in the construction thereof awater inlet tube, termed a dip tube. This tube is provided to conductcold water from the cold water inlet at the top of the storage tank downthrough the hot water in the tank to the bottom part of the latter sothat the hot water which is being drawn off from the top of the tankwill not be chilled by the inflowing cold water. These tubes areconventionally made of metal and are inserted through the water inletnipple into the tank and have at the top a flared portion which engagesthe top of the nipple to suspend the tube in place.

Use has been made recently of dip tubes formed of plastic and in orderto hold the plastic tube in position so as to prevent the top end of thetube from slipping down through the nipple, it has been proposed toemploy a means for expanding the top end of the plastic tube so that theexpanded portion may rest on the top end of the nipple. While this meansof supporting the tube has been found eflective, it has also been foundthat the projecting portion of the tube is subject to damage in theshipping of the heater so that the eifectiveness of the means employedis impaired or defeated in those cases where such part of the tube hasbecome damaged.

Means has been provided for avoiding this difliculty by having at thetop end of the plastic dip tube a unique flange structure, or byproviding a collar having a flange structure which will rest freely uponthe top end of the nipple so that the dip tube is eflfectively suspendedand prevented from sliding down into the nipple, or moving axiallyrelative to the joint. However, it has been found that where thecoupling employed for connecting the water supply pipe to the nippledoes not draw the water supply or inlet pipe down into engagement withthe flange of the collar resting upon the top end of the nipple, theplastic dip tube has a tendency to rise or fall or bounce, resulting inthe formation of noise, but in the present invention this is overcome.

In view of the foregoing, it is an object of the present invention toprovide an improved construction of a flexible dip tube, which dip tubeincludes a unique flange structure at its upper end whereby the flangewhen freely resting on the top end of a nipple or the like is secured orheld by the coupling threads so as to hold the flange and the dip tubeagainst axial movement relative to the nipple or the like within whichthe dip tube is positioned.

A further and more particular object of the invention is to provide inplastic dip tube a supporting collar and flange wherein the flange whichis adapted to rest upon the top end of the nipple through which the diptube extends, is made to have a sufiicient over-all width or diameter tolock it in between threads of the pipe cou pling so that as the couplingis threaded onto the nipple, the flange of the dip tube collar will haveits edge portion engaged between the threads of the coupling and therebyheld against movement in and axially of the coupling.

A further object of the invention is the provision in association with aplastic dip tube of an annulus secured to the top end of the tube andhaving a laterally extending atent ice flange which projects laterallyof the tube and a substantial distance beyond the outer sides thereof tobe engaged between threads of a pipe coupling attached to the nipplefrom which the dip tube is suspended, and wherein such flange may beeither circular, elliptical or have a polygonal outline and of anover-all width slightly greater than the minimum inside diameter of thethreaded pipe coupling whereby a portion of the flange will be securedbetween threads of the coupling, as stated.

The invention will be best understood from a consideration of thefollowing detail description taken in connection with the accompanyingdrawing forming part of the specification, with the understanding,however, that the invention is not confined to a strict conformity withthe showing of the drawing but may be changed or modified so long assuch changes or modifications mark no material departure from thesalient features of the invention as expressed in the appended claims.

In the drawing:

FIG. 1 is a view in side elevation oi a dip tube constructed inaccordance with the present invention;

FIG. 2 is a longitudinal section taken through the top of a hot watertank and the nipple, water inlet pipe and coupling and showing, also inlongitudinal section, the improved dip tube of the present inventionsecured in position within the nipple;

FIG. 3 is a transverse section taken substantially on the line 3-3 ofFIG. 2 illustrating the manner in which a flange of circular peripheralcontour is engaged between threads of the pipe coupling;

FIG. 4 is a sectional view corresponding to FIG. 3 and illustrating theuse of an annulus or collar having a flange of elliptical peripheralcontour;

FIG. 5 is a sectional view corresponding to FIG. 3 and showing the useof an annulus or collar having a flange of polygonal edge form;

FIG. 6 is a sectional view through the upper end of a nipple andthreaded coupling attached thereto and illustrating another dip tubeconstruction and method of locking the same to the coupling.

Referring now more particularly to the drawing, the numeral 10 generallydesignates the top portion of a conventional storage water heater tankhaving therein an opening 12 and having secured upon the top surfaceconcentric with the opening 12 an internally threaded coupling 14.

The numeral 16 designates a short nipple which is threaded at one end asindicated at 18 into the coupling and which is connected at its upperend to the water inlet pipe 20 by a conventional internally threadedcoupling or fitting 21.

The dip tube of the present invention, together with the presentimproved suspension collar or annulus, is generally designated 22.

The plastic tube body is designated 23 and the annulus or collar whichis fitted to the upper end thereof is designated 24.

The annulus 24 comprises a sleeve portion 25 from one end of whichprojects the encircling flange 26. This sleeve body portion ispreferably introduced into the upper end of the dip tube 23 and hasportions thereof struck outwardly and forced into the material of thedip tube to lock the sleeve in position therein. These outstruckportions are here shown as being in the form of tongues or fingers 26and, as stated, they are pressed or made to cut into the material of thetube body 23 with the free ends thereof directed toward the adjacent endof the tube body so that the body 25 of the annulus or collar issecurely locked in place.

The flange 26, which in the form shown in FIGS. 1 to 3 is of circularedge contour, is dimensioned to have an over-all width or diameterslightly greater than the minimum inside diameter of the coupling inglyit will be seen that when the dip tube upon the top end of the nipple,when the coupling 21 is threaded onto the nipple the edge of the flange26 Will be threaded into the coupling or Will be engaged between ment ofthe dip tube and the supporting annulus can take place within thenipple. Accordingly it will that even though the end pending annulus,dip tube can occur.

FIGS. 4 and 5 illustrate other forms which the of the dip tubesupporting annulus may have.

In FIG. 4 the dip tube supporting annulus is generally designated 24aand the flange is designated 28. This of elliptical edge contour so thatnipple after the dip tube has been placed in position and the flange 28is resting upon the top end thereof.

In FIG. 5 the dip tube supporting annulus or collar is generallydesignated 24b and the flange 29 formed integral with the top edge ofthe body of the annulus has a polygonal contour here shown as square orrectangular, although it may be three sided, if desired. In this form ofthe flange the greatest width is from corner to corner and this Widthis, of course, slightly greater than the minimum inside diameter of thecoupling 21 so that only the corners of the flange 29 will be engagedbesame manner as thin metal, as for example, fiber glass When thecoupling is threaded onto the top end of the nipple it Will be seen thatby using a thin deformable The dip tube is generally designated 33 andthe upper end portion of the same is here shown located in the upper endof the nipple and extending above the upper end of the nipple and thisupper end portion of the dip tube is expanded by an inserted annulus 34to force a I claim: 1. A dip tube structure and heater having a waterinlet the crest of the outermost interior screw-thread of the coupling,the diameter of the flange also being slightly less than the rootdiameter of the threads at the inner end of the coupling, the thicknessof the flange being less than one-half the pitch of the threads of thecoupling, the flange resting on, and free of relative to gatednon-metallic flexible tube, said ferrule being one piece and ring-likeand comprising an outwardly directed unbroken and crest of the outermostinterior screw-thread of the coupling, the diameter of the flange alsobeing slightly less than the root diameter of the threads at the innerend of the coupling, the thickness of the flange being less thanone-half the pitch of the threads of the coupling, the flange restingon, and free of rigid connection with, and capable of rotation relativeto the top end of the nipple and the tube being suspended in spacedrelationship from the inner surface of the nipple, whereby the tubedropped into the nipple with the flange resting on the said top endthereof and 'with the tube depending in the nipple and spaced from theinner surface of the same, upon tightening the threads of the couplingon the top end portion of the nipple, the dip tube is held against anyaxial movement relative to the joint by being confined between thethreads of the coupling and the top end of the nipple.

References Cited in the file of this patent UNITED STATES PATENTS

